The symbolism of the British head of state meeting Sinn Fein's leading political representative in Northern Ireland is astonishing; all the more so given the direct personal implications the 'Troubles' have had for those involved. People in Northern Ireland have witnessed many remarkable events over the past decade, events which no rational or sane person could possibly have foreseen. Wednesday's meeting will, however, resonate as one of the most memorable - a truly historical moment which made front page news around the world.

The context for the meeting was, of course, Her Majesty's immensely successful state visit to the Irish Republic last year, the first in a century for a reigning monarch. Again, Co-operation Ireland was delighted to play its part in helping pave the way for that visit by providing occasions and forums for the respective heads of state to meet. While I was confident that the visit would be well received, I was taken at just how warm the Queen’s reception was. I was also struck by the deftness and graciousness of Her Majesty's laying to rest of painful historical memories.

As we gathered to celebrate the contribution of the arts to peace building and mutual understanding in Ireland, and to witness 'that handshake', we were mindful of Her Majesty's insightful words during her speech in Dublin Castle last year. On that occasion she reminded us "that with the benefit of political hindsight, we can all see things which we wish had been done differently or not done at all". It would be difficult to find a better summation of what practical reconciliation is.

That meeting and, indeed, the vastly improved relationships in Northern Ireland are not mere accidents of fortune. They are only possible because of what has gone before. They are the outworking of the increasing warmth and strength of relationships between the two sovereign governments of Britain and Ireland, the leadership and courage of Northern Ireland's first and deputy first ministers and the industriousness and commitment of all the parties in the Northern Ireland executive who have championed tolerance, mutual understanding and respect.

'That handshake' marked another milestone the journeys of both Britain and Ireland. Those involved can be proud of the achievements, but we must not allow ourselves to be mesmerised by them. The momentum created by such visible events must be harnessed and put to work. The disease of sectarianism still permeates through Northern Irish society at every level, and its scars are the so-called Peace Walls that blight communities. At the peak of the parading season this week, its symptoms become ever more acute. The handshake is a milestone, but it is not our destination. Cooperation Ireland's projects in some of the most challenging communities mean we can measure the distance yet to travel. Our journey is towards a stable Northern Ireland, with a shared society truly at peace with itself.

We have charted our course. Now is the time to force the pace.

Christopher Moran is chairman of Cooperation Ireland, an international peace-building charity.

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